What the study found
The study found extensive baby-to-baby transmission of microbial strains in nursery groups during the first year of life. By the end of the first term, nursery-acquired strains made up a share of the infant gut microbiome comparable to strains from family.
Why the authors say this matters
The authors conclude that social interactions in infancy are crucial drivers of infant microbiome development. The findings indicate that transmission among babies, not only from mothers or families, helps shape the developing gut microbiome.
What the researchers tested
The researchers carried out a metagenomic survey, which uses DNA from mixed microbial communities to identify strains, in nursery settings. They sampled 134 people, including babies attending nursery during the first year, educators, and families, and collected 1,013 fecal samples across three facilities.
What worked and what didn't
They detected baby-to-baby microbiome transmission after only one month of nursery attendance, and the transmission network became more complex over the nursery year. Having siblings was associated with higher microbiome diversity and less strain acquisition from nursery peers, while antibiotic treatment was the condition most associated with increased influx of strains.
What to keep in mind
The abstract does not describe detailed limitations beyond the study’s nursery-based scope and first-year timeframe. The findings come from three facilities and should be read within that setting.
Key points
- Extensive baby-to-baby strain transmission was detected in nursery groups.
- Nursery-acquired strains reached a contribution comparable to family strains by the end of the first term.
- Transmission continued to increase over the nursery year in a more intricate network.
- Having siblings was linked to higher microbiome diversity and less strain acquisition from nursery peers.
- Antibiotic treatment was the condition most associated with increased influx of strains.
Disclosure
- Research title:
- Nursery peer transmission shapes infant gut microbes
- Authors:
- Liviana Ricci, Vitor Heidrich, Michal Punčochář, Federica Armanini, Matteo Ciciani, Amir Nabinejad, Farnaz FAZAELI, Elisa Piperni, Charlotte Servais, Federica Pinto, Mireia Valles‐Colomer, Francesco Asnicar, Nicola Segata
- Institutions:
- European Institute of Oncology, European Institute of Oncology, European Institute of Oncology, European Institute of Oncology, King's College London, King's College School, Universitat Pompeu Fabra, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento, University of Trento
- Publication date:
- 2026-01-21
- OpenAlex record:
- View
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